package com.raspdroid;

import android.view.View;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.AlphaAnimation;
import android.view.animation.Animation;
import android.view.animation.AnimationSet;
import android.view.animation.DecelerateInterpolator;
import android.view.animation.Interpolator;
import android.view.animation.TranslateAnimation;
import android.view.animation.Animation.AnimationListener;
import android.widget.ViewAnimator;

/**
 * This class contains methods for creating {@link Animation} objects for some of the most common animation, including a 3D flip animation, {@link FlipAnimation}.
 * Furthermore, utility methods are provided for initiating fade-in-then-out and flip animations.
 * 
 * @author Ephraim A. Tekle
 *
 */
public class AnimationFactory {
        
        /**
         * The {@code FlipDirection} enumeration defines the most typical flip view transitions: left-to-right and right-to-left. {@code FlipDirection} is used during the creation of {@link FlipAnimation} animations.
         * 
         * @author Ephraim A. Tekle
         *
         */
        public static enum FlipDirection {
                LEFT_RIGHT, 
                RIGHT_LEFT;
                
                public float getStartDegreeForFirstView() {
                        return 0;
                }
                
                public float getStartDegreeForSecondView() {
                        switch(this) {
                        case LEFT_RIGHT:
                                return -90;
                        case RIGHT_LEFT:
                                return 90;
                        default:
                                return 0;
                        }
                }
                
                public float getEndDegreeForFirstView() {
                        switch(this) {
                        case LEFT_RIGHT:
                                return 90;
                        case RIGHT_LEFT:
                                return -90;
                        default:
                                return 0;
                        }
                }
                
                public float getEndDegreeForSecondView() {
                        return 0;
                }
                
                public FlipDirection theOtherDirection() {
                        switch(this) {
                        case LEFT_RIGHT:
                                return RIGHT_LEFT;
                        case RIGHT_LEFT:
                                return LEFT_RIGHT;
                        default:
                                return null;
                        }
                }
        };
         
        
        /**
         * Create a pair of {@link FlipAnimation} that can be used to flip 3D transition from {@code fromView} to {@code toView}. A typical use case is with {@link ViewAnimator} as an out and in transition.
         * 
         * NOTE: Avoid using this method. Instead, use {@link #flipTransition}.
         *  
         * @param fromView the view transition away from
         * @param toView the view transition to
         * @param dir the flip direction
         * @param duration the transition duration in milliseconds
         * @param interpolator the interpolator to use (pass {@code null} to use the {@link AccelerateInterpolator} interpolator) 
         * @return
         */
        public static Animation[] flipAnimation(final View fromView, final View toView, FlipDirection dir, long duration, Interpolator interpolator) {
                Animation[] result = new Animation[2];
                float centerX;
                float centerY;
                
                centerX = fromView.getWidth() / 2.0f;
                centerY = fromView.getHeight() / 2.0f; 
                
                Animation outFlip= new FlipAnimation(dir.getStartDegreeForFirstView(), dir.getEndDegreeForFirstView(), centerX, centerY, FlipAnimation.SCALE_DEFAULT, FlipAnimation.ScaleUpDownEnum.SCALE_DOWN);
                outFlip.setDuration(duration);
                outFlip.setFillAfter(true);
                outFlip.setInterpolator(interpolator==null?new AccelerateInterpolator():interpolator); 

                AnimationSet outAnimation = new AnimationSet(true);
                outAnimation.addAnimation(outFlip); 
                result[0] = outAnimation; 
                
                // Uncomment the following if toView has its layout established (not the case if using ViewFlipper and on first show)
                //centerX = toView.getWidth() / 2.0f;
                //centerY = toView.getHeight() / 2.0f; 
                
                Animation inFlip = new FlipAnimation(dir.getStartDegreeForSecondView(), dir.getEndDegreeForSecondView(), centerX, centerY, FlipAnimation.SCALE_DEFAULT, FlipAnimation.ScaleUpDownEnum.SCALE_UP);
                inFlip.setDuration(duration);
                inFlip.setFillAfter(true);
                inFlip.setInterpolator(interpolator==null?new AccelerateInterpolator():interpolator);
                inFlip.setStartOffset(duration);   
                
                AnimationSet inAnimation = new AnimationSet(true); 
                inAnimation.addAnimation(inFlip); 
                result[1] = inAnimation; 
                
                return result;
                
        }
        
        /**
         * Flip to the next view of the {@code ViewAnimator}'s subviews. A call to this method will initiate a {@link FlipAnimation} to show the next View.  
         * If the currently visible view is the last view, flip direction will be reversed for this transition.
         *  
         * @param viewAnimator the {@code ViewAnimator}
         * @param dir the direction of flip
         */
        public static void flipTransition(final ViewAnimator viewAnimator, FlipDirection dir) {   
                
                final View fromView = viewAnimator.getCurrentView();
                final int currentIndex = viewAnimator.getDisplayedChild();
                final int nextIndex = (currentIndex + 1)%viewAnimator.getChildCount();
                
                final View toView = viewAnimator.getChildAt(nextIndex);

                Animation[] animc = AnimationFactory.flipAnimation(fromView, toView, (nextIndex < currentIndex?dir.theOtherDirection():dir), 500, null);
  
                viewAnimator.setOutAnimation(animc[0]);
                viewAnimator.setInAnimation(animc[1]);
                
                viewAnimator.showNext();   
        }
        
        //////////////

 
        /**
         * Slide animations to enter a view from left.
         * 
         * @param duration the animation duration in milliseconds
         * @param interpolator the interpolator to use (pass {@code null} to use the {@link AccelerateInterpolator} interpolator)       
         * @return a slide transition animation
         */
        public static Animation inFromLeftAnimation(long duration, Interpolator interpolator) {
                Animation inFromLeft = new TranslateAnimation(
                                Animation.RELATIVE_TO_PARENT,  -1.0f, Animation.RELATIVE_TO_PARENT,  0.0f,
                                Animation.RELATIVE_TO_PARENT,  0.0f, Animation.RELATIVE_TO_PARENT,   0.0f
                );
                inFromLeft.setDuration(duration);
                inFromLeft.setInterpolator(interpolator==null?new AccelerateInterpolator():interpolator); //AccelerateInterpolator
                return inFromLeft;
        }
 
        /**
         * Slide animations to hide a view by sliding it to the right
         * 
         * @param duration the animation duration in milliseconds
         * @param interpolator the interpolator to use (pass {@code null} to use the {@link AccelerateInterpolator} interpolator)       
         * @return a slide transition animation
         */
        public static Animation outToRightAnimation(long duration, Interpolator interpolator) {
                Animation outtoRight = new TranslateAnimation(
                                Animation.RELATIVE_TO_PARENT,  0.0f, Animation.RELATIVE_TO_PARENT,  +1.0f,
                                Animation.RELATIVE_TO_PARENT,  0.0f, Animation.RELATIVE_TO_PARENT,   0.0f
                );
                outtoRight.setDuration(duration);
                outtoRight.setInterpolator(interpolator==null?new AccelerateInterpolator():interpolator);
                return outtoRight;
        }
 
        /**
         * Slide animations to enter a view from right.
         * 
         * @param duration the animation duration in milliseconds
         * @param interpolator the interpolator to use (pass {@code null} to use the {@link AccelerateInterpolator} interpolator)       
         * @return a slide transition animation
         */
        public static Animation inFromRightAnimation(long duration, Interpolator interpolator) {

                Animation inFromRight = new TranslateAnimation(
                                Animation.RELATIVE_TO_PARENT,  +1.0f, Animation.RELATIVE_TO_PARENT,  0.0f,
                                Animation.RELATIVE_TO_PARENT,  0.0f, Animation.RELATIVE_TO_PARENT,   0.0f
                );
                inFromRight.setDuration(duration);
                inFromRight.setInterpolator(interpolator==null?new AccelerateInterpolator():interpolator);
                return inFromRight;
        }
 
        /**
         * Slide animations to hide a view by sliding it to the left.
         * 
         * @param duration the animation duration in milliseconds
         * @param interpolator the interpolator to use (pass {@code null} to use the {@link AccelerateInterpolator} interpolator)       
         * @return a slide transition animation
         */
        public static Animation outToLeftAnimation(long duration, Interpolator interpolator) {
                Animation outtoLeft = new TranslateAnimation(
                                Animation.RELATIVE_TO_PARENT,  0.0f, Animation.RELATIVE_TO_PARENT,  -1.0f,
                                Animation.RELATIVE_TO_PARENT,  0.0f, Animation.RELATIVE_TO_PARENT,   0.0f
                );
                outtoLeft.setDuration(duration);
                outtoLeft.setInterpolator(interpolator==null?new AccelerateInterpolator():interpolator);
                return outtoLeft;
        } 
 
        /**
         * Slide animations to enter a view from top.
         * 
         * @param duration the animation duration in milliseconds
         * @param interpolator the interpolator to use (pass {@code null} to use the {@link AccelerateInterpolator} interpolator)       
         * @return a slide transition animation
         */
        public static Animation inFromTopAnimation(long duration, Interpolator interpolator) {
                Animation infromtop = new TranslateAnimation(
                                Animation.RELATIVE_TO_PARENT,  0.0f, Animation.RELATIVE_TO_PARENT, 0.0f,
                                Animation.RELATIVE_TO_PARENT, -1.0f, Animation.RELATIVE_TO_PARENT, 0.0f
                );
                infromtop.setDuration(duration);
                infromtop.setInterpolator(interpolator==null?new AccelerateInterpolator():interpolator);
                return infromtop;
        } 
 
        /**
         * Slide animations to hide a view by sliding it to the top
         * 
         * @param duration the animation duration in milliseconds
         * @param interpolator the interpolator to use (pass {@code null} to use the {@link AccelerateInterpolator} interpolator)       
         * @return a slide transition animation
         */
        public static Animation outToTopAnimation(long duration, Interpolator interpolator) {
                Animation outtotop = new TranslateAnimation(
                                Animation.RELATIVE_TO_PARENT,  0.0f, Animation.RELATIVE_TO_PARENT,  0.0f,
                                Animation.RELATIVE_TO_PARENT,  0.0f, Animation.RELATIVE_TO_PARENT, -1.0f
                );
                outtotop.setDuration(duration); 
                outtotop.setInterpolator(interpolator==null?new AccelerateInterpolator():interpolator); 
                return outtotop;
        } 

        /**
         * A fade animation that will fade the subject in by changing alpha from 0 to 1.
         * 
         * @param duration the animation duration in milliseconds
         * @param delay how long to wait before starting the animation, in milliseconds
         * @return a fade animation
         * @see #fadeInAnimation(View, long)
         */
        public static Animation fadeInAnimation(long duration, long delay) {  
                
                Animation fadeIn = new AlphaAnimation(0, 1);
                fadeIn.setInterpolator(new DecelerateInterpolator());  
                fadeIn.setDuration(duration);
                fadeIn.setStartOffset(delay);
                
                return fadeIn;
        }

        /**
         * A fade animation that will fade the subject out by changing alpha from 1 to 0.
         * 
         * @param duration the animation duration in milliseconds
         * @param delay how long to wait before starting the animation, in milliseconds
         * @return a fade animation
         * @see #fadeOutAnimation(View, long)
         */
        public static Animation fadeOutAnimation(long duration, long delay) {   

                Animation fadeOut = new AlphaAnimation(1, 0);
                fadeOut.setInterpolator(new AccelerateInterpolator());
                fadeOut.setStartOffset(delay);
                fadeOut.setDuration(duration);

                return fadeOut;
        } 

        /**
         * A fade animation that will ensure the View starts and ends with the correct visibility
         * @param view the View to be faded in
         * @param duration the animation duration in milliseconds
         * @return a fade animation that will set the visibility of the view at the start and end of animation
         */
        public static Animation fadeInAnimation(long duration, final View view) { 
                Animation animation = fadeInAnimation(500, 0); 

            animation.setAnimationListener(new AnimationListener() { 
                        @Override
                        public void onAnimationEnd(Animation animation) {
                                view.setVisibility(View.VISIBLE);
                        } 
                        
                        @Override
                        public void onAnimationRepeat(Animation animation) { 
                        }  
                        
                        @Override
                        public void onAnimationStart(Animation animation) {
                                view.setVisibility(View.GONE); 
                        } 
            });
            
            return animation;
        }

        /**
         * A fade animation that will ensure the View starts and ends with the correct visibility
         * @param view the View to be faded out
         * @param duration the animation duration in milliseconds
         * @return a fade animation that will set the visibility of the view at the start and end of animation
         */
        public static Animation fadeOutAnimation(long duration, final View view) {
                
                Animation animation = fadeOutAnimation(500, 0); 

            animation.setAnimationListener(new AnimationListener() { 
                        @Override
                        public void onAnimationEnd(Animation animation) {
                                view.setVisibility(View.GONE);
                        } 
                        
                        @Override
                        public void onAnimationRepeat(Animation animation) { 
                        }  
                        
                        @Override
                        public void onAnimationStart(Animation animation) {
                                view.setVisibility(View.VISIBLE); 
                        } 
            });
            
            return animation;
                
        }

        /**
         * Creates a pair of animation that will fade in, delay, then fade out
         * @param duration the animation duration in milliseconds
         * @param delay how long to wait after fading in the subject and before starting the fade out
         * @return a fade in then out animations
         */
        public static Animation[] fadeInThenOutAnimation(long duration, long delay) {  
                return new Animation[] {fadeInAnimation(duration,0), fadeOutAnimation(duration, duration+delay)};
        }  
        
        /**
         * Fades the view in. Animation starts right away.
         * @param v the view to be faded in
         */
        public static void fadeOut(View v) { 
                if (v==null) return;  
            v.startAnimation(fadeOutAnimation(500, v)); 
        } 
        
        /**
         * Fades the view out. Animation starts right away.
         * @param v the view to be faded out
         */
        public static void fadeIn(View v) { 
                if (v==null) return;
                
            v.startAnimation(fadeInAnimation(500, v)); 
        }
        
        /**
         * Fades the view in, delays the specified amount of time, then fades the view out
         * @param v the view to be faded in then out
         * @param delay how long the view will be visible for
         */
        public static void fadeInThenOut(final View v, long delay) {
                if (v==null) return;
                 
                v.setVisibility(View.VISIBLE);
                AnimationSet animation = new AnimationSet(true);
                Animation[] fadeInOut = fadeInThenOutAnimation(500,delay); 
            animation.addAnimation(fadeInOut[0]);
            animation.addAnimation(fadeInOut[1]);
            animation.setAnimationListener(new AnimationListener() { 
                        @Override
                        public void onAnimationEnd(Animation animation) {
                                v.setVisibility(View.GONE);
                        } 
                        @Override
                        public void onAnimationRepeat(Animation animation) { 
                        }  
                        @Override
                        public void onAnimationStart(Animation animation) {
                                v.setVisibility(View.VISIBLE); 
                        } 
            });
            
            v.startAnimation(animation); 
        }

}